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 ###Instrução: Quantos pilotos diferentes existem que venceram montando Omr Tsunami?
 ###Tabelas: CREATE TABLE world_championship_winners (world_championship_winners_id AUTO_INCREMENT PRIMARY KEY, Year INT, Location VARCHAR, Distance (miles) INT, Rider Names VARCHAR, Horse Name VARCHAR, Best-Conditioned Horse VARCHAR) CREATE TABLE 2006_data (2006_data_id AUTO_INCREMENT PRIMARY KEY, Rank INT, Airport VARCHAR, Total Passengers INT, % Change 2005/2006 VARCHAR, International Passengers INT, Domestic Passengers INT, Transit Passengers INT, Aircraft Movements INT, Freight (Metric Tonnes) INT) CREATE TABLE doubles:_13_9_titles_4_runners-up (doubles:_13_9_titles_4_runners-up_id AUTO_INCREMENT PRIMARY KEY, Outcome VARCHAR, Year VARCHAR, Championship VARCHAR, Surface VARCHAR, Partner VARCHAR, Opponents VARCHAR, Score VARCHAR) CREATE TABLE cities_formerly_over_100000_people (cities_formerly_over_100000_people_id AUTO_INCREMENT PRIMARY KEY, City VARCHAR, State VARCHAR, 2010 population VARCHAR, Peak population (year) VARCHAR, Numeric decline from peak population VARCHAR, Percent decline from peak population VARCHAR) CREATE TABLE online_selection (online_selection_id AUTO_INCREMENT PRIMARY KEY, Artist VARCHAR, Song VARCHAR, Lyrics (l) / Music (m) VARCHAR, Votes VARCHAR, Place VARCHAR)  
SELECT COUNT Rider Names FROM world_championship_winners WHERE Horse Name = OMR Tsunami